"Biophysical properties of neurons contributing to the ability of an animal to decide whether or not to respond were examined.
B31/B32, two pairs of bilaterally symmetrical Aplysia neurons, are major participants in deciding to initiate a buccal motor program, the neural correlate of a consummatory feeding response.
B31/B32 respond to an adequate stimulus after a delay, during which time additional stimuli influence the decision to respond.
B31/B32 then respond with a ramp depolarization followed by a sustained soma depolarization and axon spiking that is the expression of a commitment to respond to food.
Four currents contributing to decision making in B31/B32 were characterized, and their functional effects were determined, in current- and voltage-clamp experiments and with simulations. ...
Hodgkin-Huxley kinetic analyses were performed on the outward currents.
Simulations using equations from these analyses showed that IK-V and IK-A slow the ramp depolarization preceding the sustained depolarization.
The three outward currents contribute to braking the B31/B32 depolarization and keeping the sustained depolarization at a constant voltage.
The currents identified are sufficient to explain the properties of B31/B32 that play a role in generating the decision to feed."
Hurwitz I, Ophir A, Korngreen A, Koester J, Susswein AJ (2008) Currents contributing to decision making in neurons B31-B32 of Aplysia. J Neurophysiol 99:814-30 [PubMed]